Pneumatic tube carrier systems are a well-known means for the automated transport of materials between, for example, an origination location to any one of a plurality of destination locations. A typical system includes a number of pneumatic tubes interconnected in a network to transport carriers between a number of user stations. Various blowers and transfer units provide the force and path control means, respectively, for moving the carriers through and from tube-to-tube within the system. One type of transfer unit allows pneumatic carries to be moved from a first pneumatic tube to a second pneumatic tube in order to route the pneumatic carrier between locations, or stations, in the network.
The pneumatic tubes that connect the various locations may be arranged in any manner that allows the carriers to be transferred between various stations. Generally, an individual station is interconnected to the network by a single pneumatic tube. In this arrangement, such a single pneumatic tube is utilized to carry carriers to and from the station. Other portions of the network are often interconnected with dedicated pneumatic tubes. It will be appreciated that the distances between stations in the network may be quite large. For instance, many pneumatic tube systems are incorporated into large facilities where the distance between the most distally located pair of stations may exceed several hundred yards or even several miles.
Within the healthcare industry, pneumatic tube systems are often used to move patient samples and drugs from a centralized dispensing or collection point to the point of analysis or use. For example, a blood sample may be drawn at a patient's bed side or at a central collection point (such as a satellite phlebotomy lab) and sent to a central lab for analysis and reporting. Similarly, a central pharmacy may receive a doctor's orders and dispense medications for distribution to a plurality of stations via pneumatic tube and then to the patients themselves via nurses positioned near the stations.
During transport, the samples and drugs are subjected to a number of physical forces. These physical forces may be systematic or random and are inherent in any transport process involving translocation from one position to the next. Examples include acceleration from a resting state at the dispatching station to a nominal average speed within the tube system followed by a deceleration at a receiving station from the average speed to a resting state and/or impact. These physical forces transfer energy to the payload (e.g., samples drugs, etc) of the pneumatic carrier.